Minato wakes up at the hospital, where Yukari watched him for a week. On their return to the boarding school, a surprise awaits them: Junpei, a talkative classmate, joins their dorm because he also seems to have "skills". Thanks to the reinforcement of these two new members, SEES can now go in search of answers in the Shadows nest, the Tartarus, a huge maze that only exists during the 25th hour.